Enquiry: How to tell whether it is the UPS or the battery that is faulty?

[Anonymous user]

Dear forum members,

I have been using the APC 650VA for about 3-5 years. During a recent power outage (when one of the fuse in the mains blew) the UPS did not function and there were no auditory warning beeps either. After the electricity supply had resumed, I proceeded to check on the UPS and noted that the On Battery indicator lamp was lit. As this event occurred some months ago, I cannot recall which colour it was nor whether it was blinking. Any how, the UPS was not providing any power to my devices nor did it seem to be charging the battery. I tried to switch off the UPS using the front panel power button to no avail. I then pushed the circuit breaker  at the back (which offered no resistance, implying that it did not trip) without any result either.

In the end, I let the battery drain itself dry and then reconnected it to the wall power socket. Only the On Battery indicator would light up dimly in orange and shimmer as if there were not enough electricity. I tried a different power cable and wall socket with the same result. Only devices connected to the Surge Only socket of the UPS (i.e. bypassing the battery) would be powered. I was wondering whether there are any tests that can be performed for me to ascertain whether it is the UPS itself or the battery that is faulty?

Thank you in advance for your assistance.

With best regards,

JC

[BillP]

Unfortunately sometimes, these units are so simple that it makes it difficult to make a judgement call on whether its the unit or battery in my opinion.

Can you get us the model from the bottom or back of the unit? i.e. BE650R or similar?

My first thought is that it is 3-5 years old so regardless, it'd make sense if it needed a new battery. If possible, I'd measure the DC voltage on the battery and see what you have there.

And I am a little confused? If you turn the unit on now while its plugged into the wall, are you say it is operating on battery power but only provides power to the surge only outlets?

[Anonymous user]

Dear Angela,

Thank you for your reply. I was neglectful and omitted to provide the model of the UPS unit. The model number is BK650E.

http://www.apc.com/products/resource/include/techspec_index.cfm?base_sku=BK650-AS

Unfortunately I do not have a multimeter and therefore I am unable to make a diagnosis on the battery itself. Although the battery might have been nearing the end of its life, one would expect the Replace Battery warning lamp to be lit under normal operating conditions (with a dying battery considered to be normal given that it is an inevitable outcome).

The description in the original post bears further clarification, but your interpretation is correct. When the UPS is now supplied with AC power, the On Battery lamp is dimly lit and shimmering, and the battery is unable to output any power nor hold a charge. The Surge Only connection, which presumably bypasses the battery completely, outputs power correctly to any connected device.

Thank you again for your reply.

JC

[BillP]

I agree - a typical UPS should notify you with a replace battery LED illuminated when the battery needs to be replaced but depending on model and what exactly has happened to it, it does not always happen. These types of units do not have super advanced battery intelligence and monitoring so the only they can do is compare the voltage drop while operating on battery to a chart with known good voltage drop values. If the battery fails catastrophically before this could occur to realize there is a problem, you could run into the situation you're seeing.

[Anonymous user · Accepted solution]

As luck would have it, I just realised that I have the BE700G-UK UPS, which shares the same BRC17 battery. Therefore, I will be able to check whether it is the unit or the battery that is faulty. I am in the middle of something right now, but will get on with it this coming weekend.